PowerColor Radeon X1800 GTO Graphics Card: the Best in Its Class?. Page 24

Today we are going to introduce to you ATI Radeon X1800 GTO graphics solution that tends to be called the best from the $199-$249 price range. The newcomer has every reason to claim this prestigious title: it features 256bit memory bus and is built on the advanced R520 GPU with the limited number of units. How tense the battle between Radeon X1800 GTO and GeForce 7600 GT is going to be? We will answer this question in our article. The newcomer will be represented by PowerColor X1800 GTO.

Futuremark 3DMark06 build 1.0.2

The situation in 3DMark06 is completely different: the performance gap between GeForce 7600 GT and PowerColor X1800 GTO is only 44 points. Moreover, Radeon X1800 XL shows very similar results despite the 16 pixel processors it features. Now let’s take a closer look at the results of SM2.0 and SM3.0/HDR tests separately.

The total score of the SM2.0 tests looks juts like the numbers we have just seen. The only difference is a slightly bigger gap between PowerColor X1800 GTO and GeForce 7600 GT. Although the gap is completely eliminated once we perform some overclocking.

As for the SM3.0/HDR tests, the advantages here lie with the PowerColor solution thanks to Radeon X1000 architecture that was designed to process pixel shaders as efficiently as possible. Moreover, the high-performance memory subsystem of the Radeon X1800 GTO gets extremely demanded in the first test of this category.

GeForce 7600 GT boasts a pretty significant performance advantage in the first SM2.0 graphics benchmark. PowerColor X1800 GTO manages to catch up only after overclocking. The remarkable thing about the first test is 26 light sources, which may be the cause of Radeon X1800 GTO’s failure. Another possible reason may also lie in the Catalyst drivers.

When we enabled FSAA and AF simultaneously, PowerColor X1800 GTO regains its leadership thanks to the 256-bit memory bus and even gets far ahead of the competitor in 1280x1024. Graphics cards with 256MB of video memory cannot handle higher resolutions in 3DMark06 with enabled full-screen anti-aliasing.

Unlike Game 2 test in 3DMark05, the second SM2.0 graphics test in 3DMark06 shows that PowerColor X1800 GTO and GeForce 7600 GT go neck and neck with one another if there is no FSAA involved. Once FSAA is enabled, PowerColor solution gets far ahead leaving GeForce 7600 GT 20%-30% behind.

The first SM3.0/HDR graphics test allows PowerColor X1800 GTO to show its best with 3.0 shader processing and HDR support. However, it loses its advantage over GeForce 7600 GT in 1600x1200. Overclocking provides about 20% performance boost for PowerColor here.

The second SM3.0/HDR graphics test doesn’t really load the memory subsystem. The most important thing here is efficient work with HDR and dynamic shadows. PowerColor X1800 GTO doesn’t support Fetch4 function that speeds up CSM shadows processing and is implemented only in R580 GPU. Besides, its graphics chip works at lower clock speed than that of the GeForce 7600 GT. As a result, Nvidia solution gets ahead. So, Radeon X1800 GTO owes its victory in the SM3.0\HDR tests category solely to the first benchmark.